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I need some help with a sudden loss of rpms

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Old Jun 20, 2009 | 02:12 AM
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From: Appleton Wisconsin
Year: 1997
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Engine: 4.0
Default I need some help with a sudden loss of rpms

So this has happened 4 times now. im driving along and all of a sudden i feel the jeep lose power, my rpm's drop to nothing. Then all of a sudden the jeep pops back up to normal rpm's and goes along just fine. I thinking I need to change my tran. filter. but i'm not sure. I also noticed that my battery is running at a lower charge then normal. Anything to help would be awesome. Thanks
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Old Jun 20, 2009 | 02:25 AM
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Originally Posted by kitsapfreerider
So this has happened 4 times now. im driving along and all of a sudden i feel the jeep lose power, my rpm's drop to nothing. Then all of a sudden the jeep pops back up to normal rpm's and goes along just fine. I thinking I need to change my tran. filter. but i'm not sure. I also noticed that my battery is running at a lower charge then normal. Anything to help would be awesome. Thanks
Trans wouldn't cause loss of power.

Sounds like a loose wiring harness somewhere. Check the grounds first thing. Might just be a loose cable.
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Old Jun 20, 2009 | 03:12 AM
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Your engine is shutting off. Either a loss of spark or fuel. Check for any damaged/corroded wiring connections and check your fuseblock for any loose or partially melted fuses.

Do all your accessories like the radio/blower motor/gauges work when the motor cuts out? IF they all die along with the engine then check your ignition switch.
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Old Jun 20, 2009 | 03:14 AM
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Originally Posted by G_P
Your engine is shutting off. Either a loss of spark or fuel. Check for any damaged/corroded wiring connections and check your fuseblock for any loose or partially melted fuses.

Do all your accessories like the radio/blower motor/gauges work when the motor cuts out? IF they all die along with the engine then check your ignition switch.
Agreed but loss of fuel shouldn't be that instantaneous. A complete fuel pump failure for 3 seconds would just result in a sputter.
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Old Jun 20, 2009 | 03:56 AM
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Originally Posted by freakaccident
Agreed but loss of fuel shouldn't be that instantaneous. A complete fuel pump failure for 3 seconds would just result in a sputter.
It might not be the pump. could be something causing the injectors to cut out for a bit. A broken wire that makes intermittent contact perhaps.
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Old Jun 20, 2009 | 06:53 AM
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Okay. So i'm okay with fab, general maintenance, and some electrical, but where should i be looking. i'll check fuses. Where are the harnesses that I should be checking?? The tranny fluid is also very dark so i'm going to still have it flushed and a new filter put in anyway. Thanks by the way a lose harness is a lot less scary then a bad tranny.
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Old Jun 20, 2009 | 06:59 AM
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From: Appleton Wisconsin
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Originally Posted by G_P
Your engine is shutting off. Either a loss of spark or fuel. Check for any damaged/corroded wiring connections and check your fuseblock for any loose or partially melted fuses.

Do all your accessories like the radio/blower motor/gauges work when the motor cuts out? IF they all die along with the engine then check your ignition switch.
I really don't remember because i had my radio off and the only blower on was to defog my windshield and its silent. I just noted the rpm gauge take a plunge. If it happens again I will remember to listen and look. It just was really bad timing because I was driving on a windy back road during a bad T-storm the last two times.
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Old Jun 20, 2009 | 07:07 AM
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take off your battery cables and clean them might just be a bad connection after that check all you groundings straps and the main battery ground
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Old Jun 26, 2009 | 11:54 PM
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update:
okay so i cleaned the battery terminals checked the main ground strap. It didn't seem to help. Now it is starting not to start right up sometimes. It clicks but nothing, then all of a sudden its just starts after a couple seconds or even minutes. Also my radio and fans do come one when i turn the key just the jeep doesn't start. Still happens when i'm driving but that doesn't seem to be getting worse... I went to go check the spark plugs but I can't get the wires off the plugs.
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Old Jun 27, 2009 | 03:39 AM
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EDIT: Starter solenoid. Replacing the starter might fix that

Last edited by freakaccident; Jun 27, 2009 at 03:53 AM.
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Old Jun 27, 2009 | 10:33 AM
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is there any way to check and see if it is the solenoid????
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Old Jun 27, 2009 | 10:35 AM
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check your alternater also. my buddies xj did this when his alternater crapped out.
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Old Jun 29, 2009 | 11:38 PM
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Okay so it also stalling now a lot.... So I think its my spark plugs and wires. I couldn't get the wires off the plugs at all. So I think they are corroded so bad that that might be the issues and me pulling on them didn't help things. If it's stalling its not the starter. The battery was at 85 percent last time i checked.
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Old Jun 30, 2009 | 12:09 AM
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I didn't see where you stated what year your Jeep was? And which engine?
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Old Jun 30, 2009 | 01:16 AM
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Kitsap, The low volts on your gauge would indicate me that your alternator is beginning to fail, easpecially since you are seeing it when driving down the road with the engine and multiple accessories running.

The fact that you can't pull your sparkplug wire boots off the plugs really disturbs me. If you have corrosion that bad at the plugs then you probably have it at the other end of the wires as well...I.E. where the plug wires connect to the dist cap and most likely corrosion on the coil contacts and coil wire or even inside the dist., as well. Corrosion at any of these points I've mentioned can put a tremendous extra load on you electrical system and cause the problems you are having.
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